It is known in the art relating to engine fuel injectors to provide a reciprocating injection valve which seats against a valve seat and is guided in reciprocation by upper and lower valve guide surfaces. U.S. Pat. No. 5,755,386 granted May 26, 1998, describes in detail the structure of one form of such injector and the construction and purposes of guiding the injection valve in such injector. Reference to this patent may be helpful in understanding both the background and structure of prior art injectors having injection valve guides.